Using CSS td width absolute, position

This may not be what you want to hear, but display: table-cell does not respect width and will be collapsed based on the width of the entire table. You can get around this easily just by having a display: block element inside of the table cell itself whose width you specify, e.g

<td><div style="width: 300px;">wide</div></td>

This shouldn't make much of a difference if the <table> itself is position: fixed or absolute because the position of the cells are all static relative to the table.

http://jsfiddle.net/ExplosionPIlls/Mkq8L/4/

EDIT: I can't take credit, but as the comments say you can just use min-width instead of width on the table cell instead.

The reason it doesn't work in the link your provided is because you are trying to display a 300px column PLUS 52 columns the span 7 columns each. Shrink the number of columns and it works. You can't fit that many on the screen.

If you want to force the columns to fit try setting:

body {min-width:4150px;}

see my jsfiddle: http://jsfiddle.net/Mkq8L/6/ @mike I can't comment yet.

You're better off using table-layout: fixed

Auto is the default value and with large tables can cause a bit of client side lag as the browser iterates through it to check all the sizes fit.

Fixed is far better and renders quicker to the page. The structure of the table is dependent on the tables overall width and the width of each of the columns.

Here it is applied to the original example: JSFIDDLE, You'll note that the remaining columns are crushed and overlapping their content. We can fix that with some more CSS (all I've had to do is add a class to the first TR):

    table {
        width: 100%;
        table-layout: fixed;
    }

    .header-row > td {
        width: 100px;
    }

    td.rhead {
        width: 300px
    }

Seen in action here: JSFIDDLE